高速铁路隧道初始压缩波一维流动模型的数值分析方法

基于隧道内空气流通截面是时间和距离的二元函数条件与一维流动理论,提出了高速列车驶入设有缓冲结构隧道端口时产生初始压缩波的数值分析方法。一维流动理论采用考虑摩擦、传热以及空气质交换等因素的一维可压缩非定常不等熵流动模型。数值分析方法采用广义黎曼变量特征线法。与国外有关未设缓冲结构、开孔型与未开孔型缓冲结构的隧道端口三种情况的现车试验结果进行了比较,表明本文所建方法正确、合理,能够模拟计算多种类型缓冲结构条件下的压缩波波动规律。

Numerical method of initial compression waves produced by a high-speed train entering a tunnel-hood based on one dimensional unsteady compressible flow model

An initial compression wave generated when a high-speed train enter tunnel entrance portal,causes an impulsive noise called micro-pressure wave.The various hoods installed at the tunnel entrance can reduce the micro-pressure wave.In this paper the initial compression wave was calculated numerically by the method of characteristics based on the equations of one-dimensional unsteady compressible non-homentropic fluid flow.The equations are capable of modelling the effects of friction,heat transfer,tunnel leakage which the cross-sectional area of the tube flow is dependent on the time and the distance.The numerical procedure is validated by measurements of tunnel-train full scale experiments of foreign high-speed railway.The validating results show that the numerical method in this paper can predicts the compression wave fronts correctly produced by a high speed train entering various tunnel-hoods.